Structural properties and thermal conductivity of Na1-xGe3+z
Winnie K. Wong-Ng, Stevce Stefanoski, James A. Kaduk, Qingzhen Huang, Clifford R. Bowers, George S. Nolas, Beekman Mathew
Structural analyses as well as low temperature thermal conductivity is reported for the new phase in the Na-Ge system, Na1-xGe3+z. Specimens were characterized by thermal analysis, conventional and synchrotron powder X-ray diffraction, neutron powder diffraction, nuclear magnetic resonance (NMR) spectroscopy, and electrical and thermal transport measurements. With structural characteristics qualitatively analogous to some aluminum-silicate zeolites, the crystal structure of this material exhibits an unconventional covalently bonded tunnel-like Ge framework, accommodating Na in channels of two different sizes. Observed to be non-stochiometric, this material concurrently exhibits substantial structural disorder in the large channels and a low lattice thermal conductivity, of interest for the identification of novel low thermal conductivity intermetallics for thermoelectric applications.
, Stefanoski, S.
, Kaduk, J.
, Huang, Q.
, Bowers, C.
, Nolas, G.
and Mathew, B.
Structural properties and thermal conductivity of Na1-xGe3+z, Journal of Physics and Chemistry of Solids
(Accessed July 31, 2021)